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SCHEDULE I - CONDENSED FINANCIAL INFORMATION - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Cash Flows from Operating Activities: |  |  |
Net cash provided by operating activities | $ 402,762 | $ 549,033 | $ 807,634
Cash Flows from Investing Activities: |  |  |
Net cash used for investing activities | (85,551) | (154,336) | (302,150)
Cash Flows from Financing Activities: |  |  |
Dividends paid to shareholders | (44,204) | (34,461) | 0
Repurchase of common shares | (100,026) | (381,040) | (491,033)
Net cash used for financing activities | (160,451) | (435,282) | (506,781)
Increase (decrease) in cash and cash equivalents | 155,314 | (36,729) | (637)
Cash and cash equivalents: |  |  |
Cash and cash equivalents at beginning of period | 351,385 |  |
Cash and cash equivalents at end of period | 506,699 | 351,385 |
Parent Company |  |  |
Cash Flows from Operating Activities: |  |  |
Net cash provided by operating activities | 0 | 0 | 0
Cash Flows from Investing Activities: |  |  |
Distribution received from subsidiary | 150,444 | 433,325 | 491,033
Distribution paid to subsidiary | 0 | 0 | 14,428
Net cash used for investing activities | 150,444 | 433,325 | 505,461
Cash Flows from Financing Activities: |  |  |
Issuance of common stock, net of taxes withheld | (6,214) | (17,824) | (14,428)
Dividends paid to shareholders | (44,204) | (34,461) | 0
Repurchase of common shares | (100,026) | (381,040) | (491,033)
Net cash used for financing activities | (150,444) | (433,325) | (505,461)
Increase (decrease) in cash and cash equivalents | 0 | 0 | 0
Cash and cash equivalents: |  |  |
Cash and cash equivalents at beginning of period | 0 | 0 | 0
Cash and cash equivalents at end of period | $ 0 | $ 0 | $ 0

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